A family gets together, the mom, the dad, all the brothers and sisters and their dates. They are at a getaway house in the woods. Then 3 masked killers arrive killing them one by one, eventually finding out 2 brothers hired those 3 killers to do the job, and the girlfriend of 1 of the brothers knew about it too, but the other girlfriend of the other brother did not, they wanted her to be the witness for when the cops (if they) arrive.
But it all goes wrong when the killers go after the brothers girlfriend, them not expecting she'd kill em all kicking their dumb asses. Then the girl and her boyfriend are just left, she kills him because she didnt believe him when he said ''You were supposed to survive, they were never gonna hurt you, only the rest''. The reason they hired them to kill their whole family is so they can inherit their parents money and the reason they also had to kill the other brother and sister is so they get it all to themselves.